Blind rivet



Oct. 17, 1950 v l.. c. HucK 2,526,235

BLIND RIVET original Filed Aug. 1o, 1942 v 2 Sheets-sheer.:

M f5 /cf' fz-62 /2 ,f4 i? //s ,sa 3:5 42 0\ 56 5;: ri/29 /V ii f5 A A ff @Mig 25 559 M f5 ,f, .f2 "g2 gd if (5? azi j' 4a i; V41! ff F5" E-E /j/ f if* g/ BY i9 MMEM,

. ATTORNEYS oct. 17, 195o l.. c. HUK 2,526,235

BLIND RIVET i Original Filed Aug. l0, 1942 2 Sheets-Sheet 2l j y \w if 3 f E INVENTOR zS (f HUC/,

. Q 7; E u n3 ATTORNEYS.

member Patented Oct. 17, 1950 assignments. 'tol-luck Manufacturing Company, Detroit, `Mich., 'a'corporation of 'Michigan `Original application August V1.0, 1942, Serial No. 454.211,'now'Patent No. 2,397,111, dated March '26,1946'. Divided and this application Novem- "ber 20, 1944,' SerialNo. 564,316

A1 The invention relates to frivetsan'dfrveting and it Yhas'particulay` relationto rivets adapted 4to 'be applied and set from onesi'de only of the struc- `ture being riveted. Y

`The present application Jconstitutes a division of mycopending application for patent, Serial No. 454,211, 'led August/*10, v1942, lnow Patent '2,397,111, issued -March '26, 1946, and :entitled Rivet and Method o'fRiveting.

One object of the invention Visto provide an fimproved two-part rivet-including a Apin and a 4tubular member lwherein means 'are 'provided for limitingmotion of the lp'in'through the tubular -Another object jof the invention is vto provide an improved method of riveting With a two-part .rivet `such as mentioned wherein "an improved lock between 'the pin vandtuhular member is Aefffecte'd through governing of Jthe pin 'forces and lpin motion.

-Another object of the invention lis to provide an improvedmethod' o'f riveting with a two-part rivet wherein, through governing voi 'pin `forces and pin motion, `a tighter relation of parts is obtained.

Other ob'jec'ts'of'the invention will become ap- `-parent ffrornlthe following `sp'eciiication,from the :drawings relating thereto, Vand from the claims hereinaftersetforth. L

For 'abetter 'understanding of the invention, reference may be "had to the, drawings, wherein; n Figure 1 is a'cross-sectional viewof a;rivetas sembly constructed according '-to 'one form lof the invention, with rivet setting apparatus engaging the rivet ,preparatory'tosetting it; i v

' Fig. 2 illustrates theassembly showniby Fig. V1

Vafter the-rivet has partly been set; igy is 'a view illustrating the 'rivet va'snally se Figs 4, 5, 6, '7 and 8 relate to another form of tthe invention and illustrate different stages in the rivet setting operation; and,

y Fig. @illustrates a rivet on theorder of that 'shown by Fig. 4, but constructed according to another form of the invention.

Referring to Fig. 1, lstructuralsheetsl or'strips to'be riveted are indicated at 'I0 and H and these have apertured dimples I2 and lf3 -Which provide'a conical recess `I5 adapted 4toreceive a Vconically formed lrivet head Vand an opening I6 for receiving the body'portion of the rivet. The method of forming the dimple and the details 'characterizingthe dimpleformati'on are disclosed 'iin my copending applications for patent Serial nlITO-lwfZllS, led April -18 1940, iraient 1 3 Claims. (Cl. `85h40) Cil 2,292,466, 'issued August Vi1, 1942,anu serial No. 352,205, led August 12,

v 1940, Vnow` Patent 2,302,772, issued November`24j1942. Mechanisms particularly adapted for forming the vdimples are disclosed and claimed in the aforesaid and vriin my copendin'g application for patent'Seri'alNo. 352,204, iiiled August 12, v19210, now Patent 2,431,935, 'issued December 2, 1947. In certain Irespects too, the rivets disclosed in the `present application for patent are similar to structures shown and disclosed in `Patents 2,292,446 and lStill referringto "Fig, "1', the rivet comprises a tubular member 2D having vafrusto-ccnical"h'ea'd r2l adapted substantiallyito fit the recess 1'5 in the sheet I'O. The external formation of this head corresponds substantially to the external-"forn1a 'tion 'of the head Vin the rivet disclosed'inPa'tent A2,302,772 above identified, andjbriy, the'head includes a conical formation "2'2accurate1y ttin'g the conical surface l5, and an outer fairing'oI` thin 'edge projection `23 which substantially contacts the sheet I0 towards the outer edge of the dimpled area. `Theparticu1ar advantages and `structural characteristics of the'two parts of the head andthe manner'in whichthe *dimple 'recess is 'formed 'and"how` it cooperates with -thewtwo parts 'of thef-head are `brought out in detail in Patent 2,'302'27-72. Whilethe rivet shown in such` copending application for patent is of one-piece character, Whereas in the present case, the rivet vis o'f two pieces, it'should be understood that the head formation described 'and the manner in which it cooperates with the dimple recess may 'be the same regardless 'of Whether the rivet is of one-pieceor two-piece character.

'Beyond the inner end of 'the-dimple portion Iin sheet H, the tubular member projects substantially soas to provide an annular Wall which may be vexpanded into va head at the inner side vor" the structure. This Wall is strainhardened by `cold Working from approximately the point 21 to theouter vend of the wall andthe strain hardening progressively A'increases as diagrammatically 'indicated by the tapered area 26, towards suchend, so as to progressively increase --the resistance of the wall to expansion. Atl the extreme outer end, the strain hardening -may be further increased so as to provide an annular section v25 which is more resistant to expansion ??lly V'16111.1911- 913 the entire wall thickness vand'that the shaded tapering area 21 is only diagrammatically illustrative of the progressive strainhardening which decreases axially from the section 25 to the point 21.

At the other end of the tubular member, the head 2| has an inner .recess 28 of conical character and at the larger end of this recess, a tubullar projection 29 or collar is joined to the head by a narrow wall 3D. At the smaller end of the recess 28, a short cylindrical surface 3| is provided and beyond this, a tapered shoulder 32 is provided which extends outwardly to a remaining, cylindrical inner surface 33 slightly larger in diameter.

A second part of the rivet comprises a pin 35 having a head 35 engaging the strain-hardened end 25 of the tubular member and the outer diameter of the head is not larger than the body part of the tubular member so that the pin and tubular member may, as an assembly, be inserted through the rivet opening I9. To the right of the head 36, the pin has a body portion 31 closely fitting the surface 33 in the body portion of the tubular member and preferably a slight press t is obtained so as to rmly hold the parts assembled. Beyond the portion 31, the pin has an annular, inwardly tapered shoulder 38 substantially corresponding in dimensions to the shoulder 32 in the tubular member and this shoulder 38 joins a short cylindrical surface 39 adapted substantially to fit within the surface 3| of the tubular member when the rivet is set. A wide angle shaped groove is provided in the pin beyond the surface 39 and is defined by side surfaces 4S and 4|, respectively. At its right r.'

end, tapered surface 4| joins a short cylindrical surface 42 substantially fitting the surface 3| on the tubular member as the parts are initially assembled, and outwardly of this surface a break neck or groove 43 is formed. The latter is deeper or rather it has the smallest trough diameter on the pin so that the pin may be broken at this point easier than at other points. Outwardly, of this groove, a substantial length of pin is provided which terminates in gripping grooves V45.

The pin comprises metal of greater hardness and tensile strength as compared to the tubular member and in connection with aircraft riveting in particular, the parts, respectively, may be made from aluminum alloys having different degrees of hardness.

The rivet is adapted to -be set by mechanism which includes jaws 59 and 5| engageable with the grooved portion 45 of the pin and these jaws are adapted to be moved by a jaw-actuating member 52. When the jaw-actuating member 52 is pulled towards the right so as to apply tension to the pin, the reactionary force first is applied through a sleeve 53 and anvil 54 to the outer face of the head 2| of the rivet. When the parts are assembled as seen in Fig. 1, sufficient tension on the pin rst will cause the head 36 to apply axial forces to the end 25 of the Vtubular member and when these forces are sulficient, the tubular projection will bulb into an annular head, as indicated at 55 in Fig. 2.

Formation of this head is controlled by the strain-hardened section 25 and this section is so designed that the bulbing will begin close to or against the work or end of the dimple I3 in sheet Moreover, the structure is such that through substantial variation in sheet thickness this desired manner of bulbing will occur. Changes in sheet thickness will, with a single length tubular Vmember, cause the projecting tubular art to vary in length and in the designed range, the length of tubular part and thickness thereof, in conjunction with the progressive strain-hardened end, will insure beginning of bulbing action close to the work and completion of bulb forming with the bulb strongly against the Work. A part of the progressively strain-hardened section may also expand depending upon work thickness, but generally the cold-worked section 25 Will remain against the pin. It may be mentioned here that the progressive strain-hardening, if desired, may extend from the point 21 all the way to the outer end of the tubular member so as to avoid any distinctive end section 25 and, in this event, a substantial end section of the strain-hardened section will remain against the pin, although it may be less in length.

Fig. 2 shows the beginning of the bulbing action. As it continues, the shoulder 38 on the pin approaches the shoulder 32 in the tubular member and nally, after the bulbed head is formed, the shoulders engage as seen in Fig. 3, so that further movement of the pin is stopped. At the same time, the cylindrical surface 39 on the pin has moved within the cylindrical surface 3| while the pin surfaces 40 and 4| have moved to positions complemental to the surface 28 in the tubular member so that these three surfaces form a conically shaped recess.

With the shoulders 38 and 32 now engaged and bulbed head formed, further movement of the pin is resisted both by the bulbed head and shoulder 32, and when the pull on the pin increases sufficiently, the riveting mechanism automatically operates to cause a secondary anvil 59 to move into engagement with the collar 29 so as to take the reaction previously taken by the anvil 54. This anvil has a tubular portion 60 which engages the collar 29 and when the reaction to the pull on the pin is taken by the anvil 59 and portion 6D, the collar 29 is sheared from the head and moves into the recess in the head along the surface 28. The latter surface guides the collar into the space defined by the surface 28 and the pin surfaces 40 and 4|, and, as a result, a positive annular lock of conical keystone character is formed between the pin and tubular member at this end of the rivet. It will be noted that the anvil 60 is free to move to the left so as to insure complete movement and upsetting of ythe inetal 29 into the locking space whereby locking engagement is fully obtained. Normally, when this occurs, the anvil portion is substantially flush with the head 22.

Setting of the rivet may be effected by riveting mechanism on the order of that embodied in Huck et al. Patent No. 2 053,719 and illustrated particularly in Fig. 9 of that patent. Operation of the mechanism is controlled by a manually actuated trigger. The primary anvil first takes the reaction to pull on the pin and then, when the pull on the pin reaches a predetermined value after forming the bulbed head, the secondary anvil functions automatically and moves against the collar'so that the reaction to the pull on the pin is taken through the latter. Reduction in pull on the pin may occur as the collar shears off and moves into the looking recess but as the collar seats in the latter the secondary anvil meets greater resistance to movement and the pull on the pin and reaction force on the anvil increase so that the locking metal or collar is strongly forced and up`et into the locking recess.

In general, it should be understood by having the progressively cold-worked end of the tubmar Although more than one form of the invention has been illustrated and described in detail,

it will be apparent to those skilled in the art that various modications may be made without departing from the scope of the appended claims,

What is claimed is:

l. A rivet comprising a tubular body means adapted to project through the opening in a structure to be riveted and having a tubular portion adapted to project beyond one side of the structure. and to be expanded into a head, a pin extending through the tubular body and having means on one end for expanding the tubular portion to form said head when the pin is moved axially in the body, said pin and body having locking means so constructed and arranged with respect to each other as to reach matching positions after formation of said head and after predetermined movement of the pin in the body, and shoulders on the pin and on the inner surface of the tubular body so constructed and arranged with respect to each other as to. engage each other after said predetermined movement so as to prevent further movement of the pin in the body.

2. A rivet comprising a tubular body means adapted to project through the opening in a structure to be riveted and having a tubular portion adapted to project beyond one side of the structure and to be expanded into a head, a pin extending through the tubular body and having means on one end for expanding the tubular portion to form said head when the pin is moved axially in the body in one direction, a shoulder on the pin positioned to expand that part of the body within the structure opening during such movement of the pin, and a second shoulder on the pin of greater diameter than the rst shoulder and positioned to'limit movement of the latter in the tubular body in said direction.

3. A rivet comprising a tubular body. means having a part adapted to project through the opening in a structure to be riveted and a second part of larger internal diameter than said rst part adapted to be located beyond one side of the structure and to be expanded into a head, an annular internal shoulder at the junction of the two parts, a pin extending through the tubular member and having means on one end for expanding the second part of the body, a shoulder on the pin positioned to expand the rst part of the tubular body to ll the structure opening, said shoulder being of such diametrical size that the internal diameter of said rst part of the tubular body, while being increased, remains smaller than the internal diameter of the second part of the body after the hole lling operation, whereby a portion of the internal shoulder at the junction of the two parts of the body remains, and a second shoulder on the pin of greater diameter than said first shoulder and positioned to engage said remaining shoulder portion in the body after the head forming and hole filling operations so as to limit the pin movement.

LOUIS C. HUCK.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENI'Sv Number Name Date 1,944,246 Langhammer Jan. 23, 1934 2,061,628 Huck Nov. 24, 1936 2,061,629 Huck Nov. 24, 1936 2,324,142 Eklund July 13, 1943 2,380,836 Gottlieb July 31, 1945 

